British vegetarian group upset that meat from culled grey squirrels is being sold at a London supermarket.

As thousands of non-native grey squirrels are slaughtered in Britain, some of the carcasses are ending up on supermarket shelves, angering animal activists, according to BBC News. But is this unusual menu item actually a sustainable choice?

Populations of Britain's native red squirrel plummeted after grey squirrels were imported from North America as an aristocratic curiosity in the 1870s. Grey squirrels are larger and more aggressive than red squirrels, and carry squirrel pox disease.

"Anyone who cares about wildlife, as I do, should be appalled at Budgens for allowing this," said Jenny Seagrove, actress and patron of Vegetarians International Voice for Animals (VIVA).

But shop owner Andrew Thornton says he's just doing his part to ensure that the death of these animals isn't wasted. He says that his branch of Budgens sells more than a dozen squirrels a week at ￡3 or ￡4 each.

"Grey squirrels are abundant in nature and are culled so it is better that they are eaten than incinerated," he told the BBC. "We are very strong on sustainability and squirrel meat takes much less to produce then say beef."

But there's some debate over whether a massive cull is the right way to deal with the grey squirrel problem.

“Red squirrel numbers can be boosted in a number of ways without harming the grey squirrel, including establishing them on islands, changing tree planting patterns and offering supplementary feeding,” reads a statement on the VIVA website.

But will squirrel meat catch on?

"I think it's lovely,” Thornton told The Guardian. “It's bit like rabbit. I think there will be a lot of fuss about this now, but in a few years it will become accepted practice that we eat squirrels. People don't bat an eyelid now about eating rabbit.”